A method and apparatus for protecting a transmitter radio frequency power amplifier

Abstract

The application discloses a protection method and device for a radio frequency power amplifier of a transmitter, the transmitter is set to maximum working power, and working current of the radio frequency power amplifier is measured and recorded; maximum current limiting of a system is obtained according to an error vector magnitude of the system and the working current of the radio frequency power amplifier, an electronic fuse circuit is configured, and the current limiting value of the electronic fuse circuit is set to the maximum current limiting of the system. The method provided by the application can protect the final stage power amplifier of the transmitter, and is simple, efficient, low in cost and the like.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication technology, and particularly relates to a protection method and device for a transmitter radio frequency power amplifier. Background Technology

[0002] Radio frequency (RF) power amplifiers are an essential component of various wireless transmitters. In the front-end circuitry of a transmitter, the RF signal generated by the modulation oscillator circuit has very low power. It needs to pass through a series of amplification and buffer stages, intermediate amplification stages, and a final power amplification stage to obtain sufficient RF power before it can be fed to the antenna for radiation. To obtain sufficiently high RF output power, an RF power amplifier must be used.

[0003] However, when base station equipment is used outdoors, it may be damaged due to antenna load failure or lightning strikes, resulting in damage to the circuits of equipment such as RF power amplifiers. At the same time, RF protection devices such as limiters and circulators are relatively expensive and their use is limited in some low-cost solutions. Furthermore, adding limiters and circulators to the circuit requires certain related instruments and debugging experience, making debugging quite complex. Summary of the Invention

[0004] In view of this, the present invention proposes a protection method and device for a transmitter radio frequency power amplifier, which can protect the final stage power amplifier, and is simple, efficient and inexpensive to debug, and can meet the long-term stable operation requirements of the equipment.

[0005] A protection method for a transmitter radio frequency power amplifier, comprising:

[0006] The transmitter was set to maximum operating power, and the operating current I1 of the RF power amplifier was measured and recorded.

[0007] The maximum current limit I2 of the system is obtained based on the system error vector magnitude and the operating current I1 of the RF power amplifier.

[0008] Configure the electronic fuse circuit and set the current limit value of the electronic fuse circuit to the system's maximum current limit I2.

[0009] The radio frequency power amplifier is the final stage power amplifier of the transmitter;

[0010] When the maximum current limit I2 of the system is obtained by measurement, the radio frequency power amplifier is powered by the first power supply alone, the system operating current is set to I1, the transmitter is set to the maximum operating power, and the current when the error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1 is the maximum current limit I2 of the system.

[0011] Configure the electronic fuse circuit, set the current limit value of the electronic fuse circuit to I2, and conduct high and low temperature tests on the system. Determine whether the measured value of the maximum current I2 is accurate by using the system performance index parameters. If the system performance index parameters do not meet the requirements, remeasure the maximum current limit I2 of the system.

[0012] The electronic fuse circuit is connected between the radio frequency power amplifier and its power supply, the first power source.

[0013] Optionally, the maximum power at the input of the power amplifier can be limited by a limiter;

[0014] A circulator connected between the amplifier output and the antenna ensures that the power amplifier is not affected by the antenna.

[0015] A transmitter radio frequency power amplifier protection device, comprising:

[0016] The acquisition module is used to obtain the system's maximum current limit I2 when the transmitter is operating at maximum power.

[0017] An electronic fuse circuit is connected between the RF power amplifier and its power supply. The current limiting value of the electronic fuse circuit is the system's maximum current limiting value I2.

[0018] The acquisition module includes:

[0019] The first measurement unit is used to measure and record the operating current I1 of the RF power amplifier when the transmitter is at its maximum operating power.

[0020] The second measurement unit is used to measure and record the system current when the transmitter's RF power amplifier is powered solely by the first power supply, the system operating current is set to I1, and the transmitter is operating at maximum power.

[0021] The determination unit is used to determine the operating current obtained by the second measurement unit as the system maximum current limit I2 when the error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1.

[0022] The detection unit is used to determine whether the measured value of the maximum current I2 is accurate when the determination unit determines the maximum current limit I2 of the system, sets the current limit value of the electronic fuse circuit to I2, performs high and low temperature tests on the system, and judges whether the measured value of the maximum current I2 is accurate through the system performance indicators; when the system performance indicators do not meet the standards, the maximum current limit I2 of the system is remeasured.

[0023] Optional, also includes:

[0024] A limiter is connected to the input of the RF power amplifier to limit the maximum power of the power amplifier;

[0025] A circulator is connected between the output of the RF power amplifier and the antenna to ensure that the power amplifier is not affected by the antenna.

[0026] The beneficial effects achieved by this invention are as follows:

[0027] The protection method and device for the transmitter radio frequency power amplifier proposed in this invention can protect the final stage power amplifier of the transmitter. At the same time, the system is simple to debug, easy to implement, simple and efficient, low cost, and can meet the long-term stable operation requirements of the equipment.

[0028] For the foregoing and related purposes, one or more embodiments include features that will be described in detail below and particularly pointed out in the claims. The following description and accompanying drawings detail certain exemplary aspects and indicate only a few of the various ways in which the principles of the various embodiments can be utilized. Other benefits and novel features will become apparent upon consideration of the following detailed description in conjunction with the accompanying drawings, and the disclosed embodiments are intended to include all such aspects and their equivalents. Attached Figure Description

[0029] Figure 1 This is a flowchart of a protection method for a transmitter radio frequency power amplifier provided in Embodiment 1 of the present invention;

[0030] Figure 2 This is a schematic diagram of the electronic fuse circuit configuration provided in Embodiment 1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the configuration limiter and circulator provided in Embodiment 2 of the present invention;

[0032] Figure 4 This is a block diagram of the transmitter radio frequency power amplifier device provided in Embodiment 3 of the present invention. Detailed Implementation

[0033] The following description and accompanying drawings fully illustrate specific embodiments of the invention to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, procedural, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Some portions and features of some embodiments may be included in or replace portions and features of other embodiments. The scope of embodiments of the invention includes the entire scope of the claims and all available equivalents thereof. In this document, these embodiments of the invention may be referred to individually or collectively with the term "invention," which is merely for convenience and is not intended to automatically limit the scope of the application to any single invention or inventive concept if more than one invention is disclosed.

[0034] Example 1

[0035] This embodiment provides a protection method for a transmitter radio frequency power amplifier, such as... Figure 1 As shown, it includes the following steps:

[0036] Step S1: Set the transmitter to maximum operating power, measure and record the operating current I1 of the RF power amplifier;

[0037] Connect the transmitter to the radio frequency load, set the transmitter to transmit-only mode, and adjust the transmit power to the actual maximum operating power.

[0038] The radio frequency power amplifier is the final stage power amplifier (PA) of the transmitter;

[0039] Optionally, the maximum power is the maximum transmit power specified in the PA datasheet;

[0040] The operating current I1 of the RF power amplifier PA of the transmitter at maximum operating power is measured using instruments such as multimeters and oscilloscopes.

[0041] Step S2: Obtain the maximum current limit value I2 of the system based on the error vector magnitude of the system and the operating current I1 of the RF power amplifier;

[0042] The operating current I1 of the RF power amplifier is adjusted by the system's error vector amplitude.

[0043] The radio frequency power amplifier PA is powered by the first power supply alone. The system operating current is set to I1. When the transmitter operates at its maximum power, the current when the system error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1 is the system maximum current limit I2.

[0044] The first power supply is a power supply with a current limiting accuracy of up to 0.1A;

[0045] Specifically, the system is set to the operating current I1 of the RF power amplifier measured in step S1, the system transmit power is set to the maximum actual operating power, the transmitter is connected to the corresponding terminal equipment (such as a comprehensive test instrument), and the error vector magnitude EVM index and actual performance of the system are measured.

[0046] The EVM threshold is EVM1. When EVM is greater than the threshold value EVM1, the current value I1 is increased. Conversely, when EVM is less than the threshold value EVM1, the current value I1 is decreased. When EVM is equal to EVM1, the current value is the system's maximum current limit I2.

[0047] The error vector magnitude threshold value EVM1 is set according to the actual needs of the system.

[0048] Step S3: Configure the electronic fuse circuit and set the current limit value of the electronic fuse circuit to I2;

[0049] The system was subjected to high and low temperature tests, and the accuracy of the maximum current I2 measurement value was determined by the system performance indicators.

[0050] like Figure 2 The diagram shows an electronic fuse (EFUSE) circuit added to the transmitter under test. The EFUSE circuit is connected between the final stage power amplifier PA and the first power supply of PA.

[0051] Set the current limit value of the electronic fuse circuit to I2, and set the overvoltage and undervoltage values ​​according to the voltage range set in the PA specification to perform high and low temperature tests on the transmitter under test.

[0052] Furthermore, the transmitter is connected to the corresponding terminal equipment and placed in a high and low temperature chamber for current testing. The high and low temperature chamber is set with the minimum and maximum temperatures required for the equipment, and the accuracy of the maximum current I2 measurement value is determined by the system performance indicators.

[0053] Optionally, the accuracy of the maximum current I2 measurement value can be determined by whether the system signal strength, error vector amplitude, and other performance parameters meet the standards. If the system signal strength, error vector amplitude, and other performance parameters do not meet the standards, the maximum current I2 measurement value is considered to be incorrect, and the above steps S1 and S2 are repeated to measure I2.

[0054] When the measured I2 value is accurate, the current limit value of the electronic fuse circuit is set to I2. When situations such as antenna short circuit or open circuit occur, the PA current will increase. When it increases to the current limit value I2, the EFUSE will consume the excess power itself. When its own temperature exceeds a certain range, it will completely shut down, thereby ensuring that the PA is not damaged and ensuring that the PA continues to work normally for a certain period of time (currently the longest tested is 36 hours). The EFUSE current and voltage limiting ensures that the PA will not be damaged and its performance remains stable.

[0055] Example 2

[0056] This embodiment provides a protection method for a transmitter radio frequency power amplifier, including the following steps:

[0057] Step S1: Measure the operating current I1 of the RF power amplifier when the transmitter is operating at maximum power;

[0058] Step S2: Obtain the maximum current limit value I2 of the system based on the error vector magnitude of the system and the operating current I1 of the RF power amplifier;

[0059] Step S3: Configure the electronic fuse circuit and set the current limit value of the electronic fuse circuit to I2; conduct high and low temperature tests on the system and determine whether the measured value of the maximum current I2 is accurate through the system performance indicators;

[0060] Step S4: Configure the limiter and circulator. The limiter limits the maximum power at the PA input terminal. The limiting parameters of the limiter are set according to the maximum input power of the PA.

[0061] A limiter flattens the signal voltage amplitude within a defined range, limiting the output signal amplitude to a certain range. That is, when the input voltage exceeds or falls below a certain reference value, the output voltage will be limited to a certain level (called the limiting level) and will not change with the input voltage. Figure 3 As shown, the limiter is connected between the preamplifier and the final power amplifier, and limits the maximum power at the PA input terminal.

[0062] A circulator is a multi-port device that directs incident waves entering any of its ports to the next port in a sequential direction determined by a static deflection magnetic field. A circulator is a non-reversible device with multiple terminals capable of unidirectional transmission of high-frequency signal energy. One end of the circulator is connected to a power amplifier (PA), and the other end is connected to an antenna and receiving devices. The circulator ensures that problems at the antenna end do not return to the PA, thus protecting the PA from antenna interference.

[0063] Impedance matching is performed between radio frequency devices. Professional radio frequency debugging instruments are used to adjust the characteristic impedance of the limiter and circulator so that the characteristic impedance meets the predetermined value within the frequency band, typically 50R, to eliminate errors caused by reflection.

[0064] Example 3

[0065] This embodiment provides a protection device for a transmitter radio frequency power amplifier, such as... Figure 4 As shown, it includes:

[0066] The acquisition module 310 is used to obtain the maximum current limit I2 of the system when the transmitter is at its maximum operating power;

[0067] The acquisition module 310 includes:

[0068] The first measurement unit 311 is used to measure and record the operating current I1 of the power amplifier PA when the transmitter is at its maximum operating power.

[0069] The second measurement unit 312 is used to measure and record the system current when the radio frequency power amplifier is powered by the first power supply alone, the system operating current is set to I1, and the transmitter is at its maximum operating power.

[0070] The determining unit 313 is used to determine the operating current of the second measuring unit as the system maximum current limit I2 when the error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1.

[0071] The detection unit 314 is used to determine whether the measured value of the maximum current I2 is accurate when the determination unit 313 determines the maximum current limit I2 of the system, sets the current limit value of the electronic fuse circuit to I2, performs high and low temperature tests on the system, and determines whether the measured value of the maximum current I2 is accurate through the system performance indicators; when the system performance indicator parameters do not meet the standards, the maximum current limit I2 of the system is remeasured.

[0072] An electronic fuse circuit 320 is connected between the power amplifier and the power supply of the power amplifier. The current limiting value of the electronic fuse circuit is the system maximum current limiting value I2.

[0073] Optionally, the device further includes:

[0074] A limiter 330 is connected to the input terminal of the RF power amplifier to limit the maximum power of the power amplifier; wherein the limiting parameter of the limiter is set according to the maximum input power of the PA;

[0075] A circulator 340 is connected between the output of the RF power amplifier and the antenna to ensure that the power amplifier is not affected by the antenna.

[0076] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0077] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0078] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0079] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

Claims

1. A protection method for a transmitter radio frequency power amplifier, characterized in that, include: The transmitter is set to maximum operating power, and the operating current I1 of the transmitter's final stage power amplifier is measured and recorded. The radio frequency power amplifier is powered by the first power supply alone. The system operating current is set to I1, the transmitter is set to the maximum operating power, and the current when the measured error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1 is the system maximum current limit I2. Configure the electronic fuse circuit, set the current limit value of the electronic fuse circuit to I2, and conduct high and low temperature tests on the system. Determine whether the measured value of the maximum current I2 is accurate by using the system performance index parameters. If the system performance index parameters do not meet the requirements, remeasure the maximum current limit I2 of the system. The electronic fuse circuit is connected between the radio frequency power amplifier and its power supply, the first power source.

2. The protection method for the transmitter radio frequency power amplifier as described in claim 1, characterized in that, Also includes: Limit the maximum power at the input of the power amplifier using a limiter; A circulator connected between the amplifier output and the antenna ensures that the power amplifier is protected from the influence of the antenna.

3. A transmitter radio frequency power amplifier protection device, characterized in that, include: The acquisition module is used to obtain the system's maximum current limit I2 when the transmitter is operating at maximum power. The acquisition module includes: The first measurement unit is used to measure and record the operating current I1 of the RF power amplifier when the transmitter is at its maximum operating power. The second measurement unit is used to measure and record the system current when the transmitter's RF power amplifier is powered solely by the first power supply, the system operating current is set to I1, and the transmitter is operating at maximum power. A determining unit is used to determine the operating current obtained by the second measurement unit as the system maximum current limit I2 when the error vector amplitude EVM is equal to the preset error vector amplitude threshold value EVM1; an electronic fuse circuit is connected between the RF power amplifier and the power supply of the RF power amplifier, and the current limit value of the electronic fuse circuit is the system maximum current limit I2; The detection unit is used to determine whether the measured value of the maximum current I2 is accurate when the determination unit determines the maximum current limit I2 of the system, sets the current limit value of the electronic fuse circuit to I2, performs high and low temperature tests on the system, and judges whether the measured value of the maximum current I2 is accurate through the system performance indicators; when the system performance indicators do not meet the standards, the maximum current limit I2 of the system is remeasured.

4. The transmitter RF power amplifier protection device as described in claim 3, characterized in that, Also includes: A limiter is connected to the input of the RF power amplifier to limit the maximum power of the power amplifier; A circulator is connected between the output of the RF power amplifier and the antenna to protect the power amplifier from the influence of the antenna.

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